docs: def active_processes(self, use_cache=True):
          """Return a list of all active processes, pruning dead ones
  
          :rtype: list
  
          """
          LOGGER.debug('Checking active processes (cache: %s)', use_cache)
          if self.can_use_process_cache(use_cache):
              return self._active_cache[1]
          active_processes, dead_processes = list(), list()
          for consumer in self.consumers:
              processes = list(self.consumers[consumer].processes)
              for name in processes:
                  child = self.get_consumer_process(consumer, name)
                  if child is None:
                      dead_processes.append((consumer, name))
                  elif child.pid is None:
                      dead_processes.append((consumer, name))
                      continue
                  elif child.pid == self.pid:
                      continue
                  try:
                      proc = psutil.Process(child.pid)
                  except psutil.NoSuchProcess:
                      dead_processes.append((consumer, name))
                      continue
  
                  if self.unresponsive[name] >= self.MAX_UNRESPONSIVE_COUNT:
                      LOGGER.info('Killing unresponsive consumer %s (%i): '
                                  '%i misses',
                                  name, proc.pid, self.unresponsive[name])
                      try:
                          os.kill(child.pid, signal.SIGABRT)
                      except OSError:
                          pass
                      dead_processes.append((consumer, name))
                  elif self.is_dead(proc, name):
                      dead_processes.append((consumer, name))
                  else:
                      active_processes.append(child)
  
          if dead_processes:
              LOGGER.debug('Removing %i dead process(es)', len(dead_processes))
              for proc in dead_processes:
                  self.remove_consumer_process(*proc)
          self._active_cache = time.time(), active_processes
          return active_processes